The field of the present invention relates to washers used for washing and aspirating the wash solution from a solid body member.
Certain types of immunologic diagnostic assays require the use of solid supports (hereinafter referred to as "beads") as supports upon which certain chemical and/or bio-chemical reactions take place. Beads can be fashioned out of glass, metal or plastics.
Certain immunologic diagnostic assays are primarily directed to measuring the quantity of material that has reacted with the sample under test. It is frequently necessary while conducting such assays to completely wash and aspirate the wash solution from beads which are resident in reaction vessels, such as test tubes, in order to remove as completely as possible the excess material which has not reacted with the sample under test. The effectiveness of such washing can directly impact the accuracy and precision of such assays. In order to achieve a thorough washing of the bead, it is necessary to wash the entire surface of the bead.
Known bead washing systems aspirate excess washing fluid through an aperture at the center of the bottom portion of the probe. Thus, the bead is drawn into stable contact with the center of the bottom portion of the probe and at least some portion of the bead will be in relatively stable contact with the probe. Although these systems are fit for their intended purposes, a stable contact point with the bottom of the probe tends to hinder the washing effect at that point and in the area immediately surrounding it.
It is desirable to provide an improved system for washing beads used as solid supports in immunologic diagnostic assays that are capable of more completely washing such beads.